The golden rules of stowage
Proper and efficient stowage is essential to avoid shifting, chafing and crushing damage. The guidelines for particular cargoes, as set out above, should be followed, and the following five Golden Rules should always be observed.
Golden Rule 1:
Before loading begins, check that there is adequate suction on all bilge lines. The date of the test and results should be appropriately entered in the deck log book.
Golden Rule 2:
A reasonable inspection of the cargo holds must be carried out before loading commences. The date and name of the vessel's officer who inspected the holds must be entered in the deck log book.
Golden Rule 3:
Never go to sea with the top horizontal tier of a steel cargo not fully completed. If the tier cannot be completed it should not be loaded, as securing with wires to the ship's sides and tomming with timber cannot be considered as proper precautions against shifting with this type of cargo and in this particular situation. In certain circumstances this rule may not apply to steel coil cargoes.
Golden Rule 4:
Steel products should never be permitted to rest against the ship's structure in stow: dunnage should always be used to prevent this occurring.
Golden Rule 5:
Underdeck steel cargoes should not be secured to component parts of the vessel's structure, with the exception of wire rod cargoes in certain circumstances (for example, half hatch stowage).
SECTION 2 - ON THE VOYAGE
Supervision of loading, stowage and discharging
Surveyors may be available to help and advise the Master but it is the Master's responsibility properly and carefully to load, stow, carry, care for and discharge the cargo. He may at some stage be obliged to prove that he fulfilled this responsibility and in doing so took all measures humanly possible to protect the cargo while it was in his custody.
The maintenance of the vessel
In negotiating cargo claims, damage caused by lack of maintenance of the vessel often leaves the carrier with no defence. As a result of this he may have to pay the claim in full or otherwise settle on very poor terms even when other factors have played an important part in causing the damage. Proper maintenance is, of course, essential.
Watertightness
Steel cargoes are almost always high density deadweight cargoes. Vessels carrying these cargoes have a high range of stability and work heavily in a seaway, imposing concentrated stresses in various areas of the hull structure; especially in the area of the hatchways. If the hatches are to remain watertight it is essential that all component parts of the steel hatch closing appliances are maintained to a high standard. This also applies to all other main deck openings.
Ventilation
Most moisture damage and subsequent rust damage to steel cargoes is caused by cargo sweat and/or ship sweat. Steel loaded in a cooler climate going to or through a relatively warmer climate will, if ventilated, probably suffer from cargo sweat (that is, condensation of moisture directly onto the actual cargo). On the other hand, when a ship travels from a warm area to a relatively cooler area, the steel cargo is vulnerable to being affected by ship sweat (that is, condensation forming on the component parts of the ship's structure within the cargo holds dropping back onto the cargo) if proper ventilation does not take place.
Steel cargoes should therefore not be ventilated when passing from a cool climate to a relatively warm climate. Cargo should be given full ventilation when temperatures are falling. It will therefore be necessary to maintain temperature records from the commencement of loading up to completion of discharge. These records will enable the carrier to prove that all necessary measures were taken to care for the cargo during the course of the voyage. In the negotiation of cargo claims it is of great importance that correctly kept records are available which will accurately and acceptably correspond with the manner in which the ventilation was used.
When it is decided that the cargo should not be ventilated every effort must be made to seal off the cargo hold from the outside atmosphere. The aim should be to make the cargo hold as air-tight as possible. If cargo hold dew point temperatures are closely following outside atmospheric dew point temperatures, then the exercise is not working: hold sealing arrangements should be re-checked.
If there is any leakage of hatches, however slight, or the ingress or presence of free moisture in the cargo hold (for example, due to a flood back along bilge lines, the ingress of rain during loading, the presence of other cargo loaded in a wet condition, or the cargo holds not being dry when loading commences), there will be an appreciable increase in the relative humidity of the ambient air surrounding the cargo, resulting in copious cargo sweat and ship sweat, possibly accompanied by serious cargo damage.
Some Owners/operators equip their ships with either permanent or portable cargo hold dehumidification units which have proved to give satisfactory results.